1. Field of the Invention
The present invention relates to a light-triggerable thyristor having a semiconductor body which contains an n emitter contacted by a cathode electrode and an adjacent p base, with a p emitter contacted by an anode electrode and having an adjacent n base which is, in turn, adjacent to the p base, and in which thyristor a projection of the p base extends up to the boundary surface adjacent a projection of the n base which likewise extends up to the boundary surface, and to a method for operating such thyristor.
2. Description of the Prior Art
A thyristor of the type set forth above is known from the book of W. Gerlach, entitled "Thyristoren", published by Springer-Verlag, Berlin, 1979, pp. 393-394. Here, a projection of the n base extends up to the boundary surface of the semiconductor body and is directly illuminated during ignition. Under the influence of a sufficiently-high forward voltage, the space charge zone which is built up at the pn junction between the p base and the n base nearly completely fills the projection of the n base. This produces a good efficiency in the illumination-dependent generation of electrons and holes from which the gate trigger current derives, so that the thyristor has a good photosensitivity.